The invention concerns a method for training adjustment in sports, particularly running sports. The invention furthermore concerns an apparatus for execution of the method.
To generate muscle power, a muscle, specifically a human muscle, requires oxygen that must be supplied by the organism. The greater the power, the greater the need for oxygen. At a certain power limit, the body will go into what is known as “oxygen debt”. This means that the blood contains too small of an oxygen ratio to be able to supply the oxygen necessary to generate power. The metabolism in the muscle then passes into the anaerobic range marked by oxygen deficiency. In contrast to this, the metabolism given sufficient oxygen supply is designated as aerobic.
Complete burning of the energy carrier glucose drawn on by the body does not ensue in the muscle in the anaerobic range. As a result of this, “combustion shortfalls” accumulate in the body that can no longer completely metabolized as a result of the oxygen deficiency. The muscle thus stressed becomes “acidic” and requires a longer time in order to regenerate after the stress.
In sport types that are connected with high body stress, particularly running sports, it is therefore important that the training is implemented predominantly in the aerobic range, and only a small portion in the anaerobic range. In an amateur athlete, for example, the aerobic training phase should amount to approximately 80% of the overall training.
For training adjustment, it is typical in sports medicine to determine the “lactate balance point” (LBP). Lactate (lactic acid) is a metabolic product of glucose that—as specified previously—is created when the oxygen in the organism is no longer sufficient for combustion. In the anaerobic range, lactate therefore accumulates in the body, while in the aerobic range excess lactate is metabolized again.
At the threshold between aerobic metabolism and anaerobic metabolism, the lactate level in the organism remains in balance. This defines the LBP. In reverse, the LBP is subsequently used as a synonym for the performance threshold at which the metabolism of the test subject passes from the aerobic range into the anaerobic range. The LBP is approximately characterized by associated measurement quantities of the organism, for example, an associated heart rate. If the heart rate of an athlete corresponding to the LBP is known, the athlete can optimize his training accordingly.
In running sports, a wearable pulse sensor is frequently used that determines the heart rate by way of a pulse band worn on the upper body of the athlete. However, using this pulse sensor, only a comparably rough training adjustment is possible. Using only the heart rate, only an imprecise estimate can be made as to whether the athlete temporarily undershoots or overshoots the LBP, and thus whether the athlete is temporarily located in the aerobic or anaerobic range.
The LBP can be determined via direct measurement of the lactate value. The lactate value is conventionally determined with a lactate measurement device which effects an analysis of blood that is extracted from the athlete at different degrees of stress. Physiological fundamentals and a method for lactate measurement are, for example, specified in German Patent Document No. DE 199 09 852 A1. The known solution is, disadvantageously, an invasive method, especially as blood samples must be extracted from the athlete to be tested (hereinafter, “test person”). This is, on the one hand, sometimes painful for the athlete. On the other hand, the blood extraction is always connected with a risk of infection, for example, with hepatitis or HIV, for both the test person and for the examiner. To reduce this infection risk, high hygiene standards are in turn necessary that make the method elaborate and expensive.